
4.6 Packet Commands
4.6.19 START/STOP UNIT command
Table 4.107 START/STOP UNIT command
Bit | 7 | 6 | 5 |
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| 2 | 1 | 0 |
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0 |
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1 | Logical Unit Number |
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| IMMED | |||
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4 |
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| LoEj | Start | |
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| Reserved |
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The START/STOP UNIT command ejects media or starts and stops rotating the disk.
When the IMMED (Immediate) bit is 1, command completion is reported before processing is completed.
Processing for other values is listed in Table 4.108.
Table 4.108 START/STOP/EJECT processing
LoEj | Start | Processing |
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0 | 0 | Stops disk rotation. |
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0 | 1 | Starts disk rotation and checks the format type of media. |
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1 | 0 | Ejects media if possible. |
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1 | 1 | Ends abnormally (ILLEGAL REQUEST). |
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